This invention relates to integration means, and more particularly to a device added to a firearm for incorporating ancillary equipment.
As the field of combat and commercial weaponry expands, numerous add-on enhancements have become available for attachment to standard firearms thereby significantly upgrading the capability of the firearm. Various methods and means have been developed for interfacing the various add-on enhancements to firearms. Applicant's U.S. Pat. No. 4,845,871, discloses a quickly detachable interface means for modular enhancements. Applicant's U.S. Pat. No. 5,142,806 discloses a universal receiver sleeve having an upper interface portion with standard, universal dimensions regardless of the firearm and having a lower interface portion specific to a particular firearm. Applicant's U.S. Pat. No. 5,343,650 discloses an extended rigid interface frame with upper and lower rails joined to a firearm receiver and extending forward about the firearm's barrel to a head assembly replacing the firearm's normal front sight. A weaver type interface return portion is provided below the barrel from the head assembly to the receiver. A yoke braces the extended rigid frame receiver sleeve of the present invention to the forward portion of the firearm's receiver. The distal end of the extended rigid frame receiver sleeve terminates in a front sight housing which connects the upper and lower rails and provides a housing for advanced laser and sensor components, and the standard front sight bead. The front sight housing is self-supported by the connection of the upper and lower rails running back to the yoke and secured to the top of the receiver. The barrel of the rifle is free floating in that it does not touch the extended rigid frame receiver sleeve in any manner. This permits greater shooting accuracy and protects sensitive electrical components within the front sight housing by isolating the front sight housing from the heat generated from the barrel. Protective spring-loaded handguards are incorporated into the extended rigid frame receiver sleeve, thereby protecting a user's hands from a hot barrel, eliminating any pressure on the barrel, and providing quick access to the barrel area.
Although the principles of the above identified patented devices are generally applicable to all firearms, the specific firearm example identified in each patent was the U.S. military M16 rifle and carbine. The M16 has been in service for a number of years and will continue to be a popular rifle both in the U.S. military and foreign military for the foreseeable future. However, with the increasing development and refinement of laser technology, it has become highly desirable to integrate laser technology capabilities onto and into firearms.
The problem with integrating laser technology to firearms is the inherent conflict between a gun barrel's physical functioning and the rigid environment required for laser operations. For maximum results, a gun barrel should be physically isolated, i.e., “floating”. It is preferred that nothing be attached to the gun barrel, thereby isolating the barrel physically and eliminating bending and “droop” along the barrel's longitudinal axis. The ideal arrangement for lasers and ancillary optics and electronics is one of complete isolation from the gun barrel. The temperature of a gun barrel in use can rise to 900° F. This type of heat, as well as the physical shock on the gun barrel from firing, will quickly destroy lasers and ancillary optics and electronics.
The heat generated by the gun barrel transfers directly to any devices touching it thereby directly transferring enough heat to burn hands and destroy attached electrical devices. Further compounding this problem is the requirement that gun barrels be extra heavy to support the added weight attached by means of the collars. This in turn means more cantilevered stress on the barrel where it is joined with the M-16's aluminum receiver. The combination of heat and barrel weight tend to pull the barrel chamber out of alignment with the bolt lead, thereby causing bolt lug and extractor failure.